On Mon, 2010-03-29 at 13:47 +0100, Stephane Eranian wrote:> On Mon, Mar 29, 2010 at 1:20 PM, Peter Zijlstra <a.p.zijlstra@chello.nl> wrote:> > The LBRs are relatively cheap to keep enabled and provide some history> > to OOPSen, also some CPUs are reported to keep them over soft-reset,> > which allows us to use them to debug things like tripple faults.> >> > Therefore introduce a boot option: lbr_debug=on, which always enable> > the LBRs and will print the LBRs on CPU init and die().> >> > When this is enabled, it will prevent changing the LBR configuration to> record only selected branches. Unless you are willing to accept filtered> content in the kernel dump.

Sure, but since we don't support that silly config reg anyway that'spretty much not an issue ;-)